Slip



July 23, 1929- w. G. CHRISTIAN 1,721,689

v Filed Aug. 2l. 1926 Patented July 23, 1929.

PATENT GFFICE.

WALTON G. CHRISTIAN, OF HOUSTON, TEXAS.

SLIP.

Application filed August 21, 1926.

This invention relates to new and useful improvements in a slip.

One object of the invention is to provide a'pipe engaging slip adaptedto seat in the opening or a rotary table of a rotary drilling machineand engage with the drill stem, or other pipe, extending through saidopening into a well bore, to hold said stem, or pipe, suspended in thebore.

Another object ot the invention is to provide a slip, of the characterdescribed composed of a plurality, preferably two, of sections, eachsection having a plurality of independent pipe engaging segments capableot independent circumferential movement and movable simultaneouslyvertically and radially.

A further object ot' the invention is to provide a slip ot' thecharacter described which is easily released trom the pipe or drillstem.

A still jturther feature of the invention resides in a slip comprising aplurality of sections, each section having a plurality of segments and ahandle connected to the segments in a novel manner, and through whichthe section may be bodily moved or handled.

lV ith the above and other objects in view this invention has particularrelation to certain novel ifeatures or' construction, operation andarrangement oit parts, an example of which is given in this,specification and illustrated in the accompanying drawings, whereinFigure l shows a plan view of one section or the slip.

litigare shows a sectional view taken on the line 2 2 ot Figure 1, and

Figure 8 shows a sectional view taken on theline 5 3 of `Figure 1.

Referring now more particularly to the drawings, wherein like numeralsof reference designate similar parts in each of the lignres, the numerall designates a segment holder, arcuate in cross sectional contour andwhose outer side tapers downwardly to con'l'orm to and seat in thedownwardly converging, pipe receiving opening, of the conventionalrotary table oit any well known type o i rotary drilling machine.lVithin this holder are the end segments 2 and the intermediate segment3, there being a plurality, preferably three, ot segments in eachholder. Each holder with its segments, con- Serial No. 130,630.

stitute a section of the complete slip. It is to be understood that acomplete slip comprises, prelerably two sections complementary to eachother, and which, when assembled in the rotary table opening, surroundand grip the stem or pipe to be suspended.

Each holder 1 has the upper and lower arcuate inwardly extending flanges4 and 5 between which the segments 2 and 3 are located and the segmentsare of such lengt-hs as to have a limited amount of vertical movementbetween said flanges. There are pins 6 secured to the lower ends ol' thesegments 2 which worl; loosely through the bearings 1" in the lowerflanges 5 and eyebolts 8, 8, work loosely through bearings 9, 9, ot theupper flanges 4 and are connected to the upper ends of these segments 2.

There is a bail l() for each section of the slip. This bail is U-shapedwith the free ends of its arms outturned and Working through the eyes ofthe eyebolts 8. This bail forms a handle through which its section maybe bodily handled, as a unit.

The inner face of each segment is shaped to engage the suspended pipe,and the outer side-oi: each segment tapers downwardly to conform to thedownward taper of the inner side ot the corresponding holder l.

Upper and lower dowel pins 11 and 12 are provided to support theintermediate segment 3 in substantially transverse alignment with thesegments 2. These pins may .be anchored to one ot these respectivesegments and project into sockets as 13, in the opposing iace oi theother segments in which said projecting ends lit loosely. The segmentsare thus permitted to move circumerentially relative to each other inthe holder, iut move substantially in unison, vertically and radially.

lVhen the slip sections are held by the handles 10 the segments will beheld in upper position relative to their holders with their upper endsabutting the flanges et. In

this position the complementary sections or" the slip are simultaneouslyseated in the rotary table opening around the pipe while said pipe issuspended by a cable and tackle block from the dei-rick, in the usualway. As the pipe is now lowered the segments will engage it and movedownwardly in the holders, meanwhile moving inwardly and wedging betweenthe pipe and the slip lll holders l, until the load of the pipe iscompletely assumed by the slips and the pipe is held suspended in thebore.

What I claim is:

1. A slip composed of a plurality of independent sections, each sectionincluding a holder whose outer and inner surfaces taper downwardly,upper and lower abutments on the inner face of said' holder, a pluralityof pipe engaging segments between said abutments and having a limitedvertical movement with respect thereto, the lower ends 'ot said segmentsand the opposing lower abutment being provided, one with pins and theother with bearings through which said pins work.

2. A slip composed of a plurality of independent sections, each sectionincluding a holder whose outer and inner surfaces taper downwardly,upper and lower abutments on the inner face of said holder, a pluralityof segments between said abutments and having a limited verticalmovement with respect thereto, said upper abutment having bearings, abail and means working through said bearings andconnected to thesegments beneath and having a pivotal connection with the respectiveends of said bail.

3. A slip composed of a plurality of independent sections, each sectionincluding a holder whose outer and inner surfaces taper downwardly,upper and lower abutments on the inner face of said-holder, a pluralityof segments between said abutments and having a limited verticalmovement with respect thereto, the lower ends of some of Said segmentsand the opposing lower abutment being provided, one with pins and theother with bearings through which said pins work. the upper abutmenthaving bearings, a bail,

and `means working through said upper bearings and connected to thesegments beneath and having a pivotal connection with the respectiveends of said bail.

el. A pipe holding slip composed of a plurality of independent sections,each section including a holder whose outer and inner sides convergedownwardly, upper and lower inside abutments in eachholder, and aplurality of wedge shaped segments arcuate in cross section between saidabutments and whose inner surfaces are shapedito engage said pipe, meansretaining some of said segments in said holder, dowel pins between thesegments so retained and the adjacent segment, each dowel pin beinganchored at one end to one of said segments and the opposing face of theadjacent segment having a socket into which the other end of said pinfits loosely.

A pipe holding slip composed of aplurality of independent sections, eachsection including a holder whose outer and inner sides convergedownwardly, upper and lower inside abutments on each holder, a pluralityot wedge shaped segments arcuate in cross section whoseinner iiaces areshaped to engage said pipe, means retaining some of said segments insaid holder, dowel pins betweenthe jaws so retained and the adjacentsegment, each dowel pin being anchored at one end to one of saidsegments and the opposing face of the adjacent segment having a soci-:etinto which the other end ot' said pin iits loosely and a handle flexiblyconnected to the end segments of said section.

in testimony whereof I have signed my name to this specification.

VALTON G. CHRISTIAN.

